You hear a lot about mercury contamination in fish, specifically shark and tuna, but researchers in New York’s Catskills have uncovered alarming amounts of mercury in the blood and feathers of bald eagle chicks. And the toxin build up is happening faster than the eagles can get rid of.

This is bad for a couple reasons. Similar levels of mercury accumulation have been associated with reproductive problems in other parts of the Northeast. And since bald eagles are so sensitive to contamination, they are good barometers for the overall health of an environment.

Coal is being blamed. Coal-burning plants release mercury. And when the wind blows it eastward it ends up in lakes, rivers and streams, contaminating the fresh water fish that bald eagles feed on with methylmercury, which can lead to neurological disorders in both animals and humans.